SHARED MEMORY AND SHARED MULTIPLIER PROGRAMMABLE DIGITAL-FILTER IMPLEMENTATION

摘要

An integrated circuit for implementing a digital filter has a data memory (100); the data memory (100) having two ports (210, 220) to permit the access of two data samples at the same time, and a coefficient memory (105) for storing filter coefficients. A first adder (110) adds data samples from first and second data memory ports (210, 220); a multiplier (115) multiplies a value from the first adder (110) by a value from the coefficient memory (105); and, a second adder accumulates values from the multiplier (115). A master controller (190) is provided configured for selectively storing the accumulated values in the data memory (100) for further processing or outputting the accumulated values. An address and control block (125) communicating with the data memory (100) and the coefficient memory (105) holds values appropriate to the filter to be executed. The address and control block (125) has two sets of a first set of registers for holding values for a first pre-determined digital filter and a second pre-determined digital filter in cascade. The method maintains a current write address for data in the address and control block (125) as a circular list, where the circular list has a size equal to a predetermined number of filter taps;. The method maintains a first read address for data from the first port as a first-in-first-out queue, a second read address for data from the second port as a last-in-first-out stack, and a coefficient read address as a circular list.